[H]OC1=C(C2=C3C(O[C@@](O[H])(C(=O)OC([H])([H])[H])C([H])([H])[C@@]3([H])O[C@]([H])(C([H])([H])[H])[C@@]2([H])C([H])([H])[H])=C1[H])C([H])([H])[H]